Carfilzomib, Lenalidomide and Dexamethasone (KRd) Vs Bortezomib, Lenalidomide, and Dexamethasone (VRd) As Induction Therapy in Newly Diagnosed High-Risk Multiple Myeloma

Background: Bortezomib, lenalidomide, dexamethasone (VRd) and carfilzomib, lenalidomide, dexamethasone (KRd) are standard induction regimens for the treatment of newly diagnosed multiple myeloma (NDMM). The phase III ENDURANCE trial excluded patients with high-risk NDMM (HR-NDMM) and included patients with no intention for immediate autologous stem cell transplant (ASCT) (Kumar SK, et al. Lancet Oncol 2020). Herein, we examined outcomes associated with KRd and VRd induction in the management of HR-NDMM. Methods: We conducted a retrospective chart review study with 154 consecutive HR-NDMM patients treated with VRd and KRd at MSKCC between 1/1/2015 to 12/31/2019. Only patients with high-risk (HR) cytogenetics defined as 1q+, t(4;14), t(14;16), t(14;20), and/or del(17p) were included. The cutoff date for analysis was 8/18/21. Early transplant was defined as ASCT within 6 months of completing induction. Primary endpoint was progression-free survival (PFS). Discrete patient characteristics were summarized by frequency (percentage) and continuous characteristics were summarized by median (IQR). PFS and overall survival (OS) were evaluated by Kaplan-Meier method. Multivariable Cox models were fitted with pre-specified clinical parameters including age, cardiac history, R-ISS stage, best response to induction, early ASCT (both time dependent covariates), and induction regimen. Results: Baseline characteristics of the 67 VRd and 87 KRd treated patients are summarized in table 1. There were 51 (76%) patients in the VRd group and 63 (72%) patients in the KRd group with 1 HR cytogenetic abnormality. Sixteen (24%) and 24 (28%) patients in the VRd and KRd groups, respectively, had ≥2 HR cytogenetic abnormalities. Among the HR-NDMM patients, 32 VRd- and 48 KRd-treated patients received early ASCT. Overall response rate by the end of induction was 93% and 98% for VRd and KRd, respectively, including 66% with ≥VGPR in the VRd group and 80% in the KRd group. Median follow-up for the entire patient population was 42.5 (IQR, 37.5-50) months with 47.9 (42.5-53.9) months for the VRd group and 37.6 (35-50) months for the KRd group. The median PFS for HR-NDMM patients treated with VRd induction was 42.6 months (95%CI, 32.8-62) and was NR (95%CI, 45.5-NR) for the KRd group (HR=1.84; 95%CI, 1.11-3.06; P=0.02) (Fig. 1). We conducted a multivariate analysis for important clinical variables that may affect survival outcomes. Multivariable analysis for PFS showed that KRd induction (HR=1.80; 95%CI, 1.05-3.10; P=0.033) and R-ISS Stage I compared to R-ISS Stage II (HR=2.67; 95%CI, 1.33-5.38; P=0.006) and R-ISS Stage III (HR=3.51; 95%CI, 1.02-12.07; P=0.046) were associated with better PFS. Early ASCT was not associated with improvement of PFS on multivariable analysis (P=0.30). Age, cardiac history, and achieving CR/sCR or VGPR/PR compared to